Apparently a recent fix made it impossible for two empires to share the same name (can't start a new game with the same name of an existing empire), presumably to prevent false flag attacks or similar.

It seems whatever list is used to store these names isn't properly cleared after an empire abdicates, meaning that if an empire is destroyed or abdicates, its name can never be used again in that scenario. The same is true for emperor name.

Unsure if this is intended behavior?

Could potentially be abused by a player/bot rapidly creating and abdicating empires with popular names, "locking them out" permanently for that scenario.

This happened to me as well. This forced me to use generation title if I want keep my username.
From "DigaRW I" to "DigaRW VI".

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